As German filmmaker Werner Herzog portrayed in his 2007 documentary Encounters at the End of the World, over the years Antarctica has enticed thousands of adventurers to explore its inhospitable geography – a surreal realm of extremes so great they cannot be understood until they are experienced.

They visit in
an effort to grasp how this strange, harsh place, where unruly blizzards and
-50C temperatures are the norm, can sustain a vital ecosystem. And their
voyages help the rest of the world understand how the frozen continent of
Antarctica works.

The first
commercial tours to Antarctica date back to the 1950s, but tourism really took off with the
formation of the International Association of
Antarctica Tour Operators in 1991, after which numbers rose from a few thousand visitors each
year to tens of thousands of annual tourists, reaching about 34,000 visitors in 2011. Many of them come on cruise
ships, often passing through Chile or Argentina first, but there are also more
than a dozen research stations on the continent, the largest being the McMurdo Station in the south, which can support more than
a thousand people.

About 14 million years ago, a period of climate change caused
the formation of the Antarctic ice sheet, which averages one mile in thickness
and gets up to three miles thick in some parts. Before this, scientists believe, Antarctica looked more like Alaska
or the Alps, consisting of a range of glacier-capped mountains. Today, the ice
sheet provides habitat for many species of seabirds, seals and penguins.

Antarctica’s
waters are home to a thriving ecosystem driven by phytoplankton -- microscopic plant-like
organisms that grow rapidly during the summer months of near-constant sunlight.
Krill (crustaceans resembling prawns) subsist on phytoplankton and are in turn
eaten by fish, squid, jellyfish, seabirds, penguins, seals, whales and other
animals. Penguins, seals, birds and whales also eat fish and sometimes
jellyfish; leopard seals will additionally eat penguins and other seals; and
orca whales will additionally eat penguins, seals and smaller whales.

New species are being discovered in Antarctica all the time. This year, for
instance, scientists discovered deep-sea hot springs (or “hydrothermal vents”)
which opened up a world of never-before-seen
wildlife, including a
new type of fuzzy and colourless Yeti crab, a still unnamed colourless octopus and a carnivorous seven-legged sea star,
all of which live in complete darkness 2,400m underwater.

But the Antarctic Peninsula is also one of the most rapidly warming regions on
the planet, and as a result, has attracted close study by climate scientists.
As the British Antarctic Survey
organisation explained,
while the “global significance of the Antarctic Peninsula warming is difficult
to assess, the main concern is for the loss of a unique landscape and biota.”

PracticalitiesTourists only visit Antarctica during the summer months of November
through March, and even then temperatures don’t typically rise above 2C. The
weeks around Christmas, however, yield a period of 24-hour
sunlight. The most common way to get to Antarctica is by ship
-- on a group tour or as part of a cruise -- and there are a number of sea
and air operators offering trips to the frozen continent. Most flights
leave from Punta Arenas, Chile, and most boat trips leave from Ushuaia, Argentina.

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